What do you use to clean grout on a honed marble floor?

I have a honed Carrera marble floor in my master bath. Every product I have tried etches the marble (if it works at all) or the grout looks just the same after scrubbing. I have tried many natural solutions off of Pinterest and retail products with zero results (one worked well but etched the tile) and it's getting frustrating. Does anyone know what will work without damaging the stone?
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